Segment Information - Net Revenue From External Customers and Intercompany Revenue From Each Operating Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total net revenue	$ 2,461.7	$ 1,809.8	$ 1,597.2
Operating Segments | Live and Historical Racing
Segment Reporting Information [Line Items]
Total net revenue	1,047.3	614.6	409.1
Operating Segments | TwinSpires
Segment Reporting Information [Line Items]
Total net revenue	444.9	436.4	451.4
Operating Segments | Gaming
Segment Reporting Information [Line Items]
Total net revenue	968.6	755.9	695.4
All Other
Segment Reporting Information [Line Items]
Total net revenue	$ 0.9	$ 2.9	$ 41.3